This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Evaluate the rates of HIV production and clearance after initiating or discontinuing antiretroviral treatment. Evaluate the dynamics of different virus populations (according to resistance pattern or host cell) after initiating or discontinuing antiretroviral treatment. Evaluate viral populations in lymph tissue in subjects with and without detectable HIV RNA in the plasma, and evaluate viral populations in lymphocytes when HIV RNA levels are undetectable in the plasma.